SPC Day 2 Thunderstorm Outlook Issued 1730Z 20040115

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ZCZC SPCSWODY2 ALL
ACUS02 KWNS 151742
SPC AC 151742

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1142 AM CST THU JAN 15 2004

VALID 161200Z - 171200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 SSW GDP INK CDS
END JLN 10 ENE POF DYR 10 W UOX GWO 10 S LUL 40 SE HUM.

...NO SVR TSTM AREAS FORECAST...

WHILE COLD POLAR LOW BEGINS TO LIFT OUT OF THE CANADIAN MARITIMES/
NORTH ATLANTIC COAST...MODELS SUGGEST LARGE SCALE TROUGH...NOW OVER
BAJA AND THE NORTHERN MEXICAN PLATEAU...WILL REDEVELOP EAST
NORTHEASTWARD ACROSS THE RIO GRANDE VALLEY FRIDAY/FRIDAY NIGHT. 
INFLUX OF MID/HIGH-LEVEL MOISTURE OFF THE LOWER LATITUDES OF THE
PACIFIC...NORTHWARD RETURN OF LOW-LEVEL GULF MOISTURE...AND
STRENGTHENING LARGE-SCALE ASCENT AHEAD OF SOUTHERN TROUGH LIKELY
WILL SUPPORT WIDESPREAD PRECIPITATION WITH EMBEDDED CONVECTION
ACROSS THE SOUTH CENTRAL STATES.

...TEXAS...
CORE OF COLDEST MID-LEVEL AIR IN SOUTHERN BRANCH TROUGH IS
ASSOCIATED WITH SHORT WAVE TROUGH NOW DIGGING OFF THE CALIFORNIA
COAST. THIS AIR MASS IS PROGGED TO REMAIN OVER THE MEXICAN PLATEAU
THROUGH MUCH OF THE FORECAST PERIOD...WITH DOWNSTREAM MID-LEVEL
THERMAL RIDGE TENDING TO LIMIT STEEPNESS OF LAPSE RATES AND
MAGNITUDE OF CAPE DEVELOPING WITH MOISTURE RETURN ACROSS THE
SOUTHERN PLAINS/LOWER MISSISSIPPI VALLEY REGION.  THUS...CONVECTIVE
DEVELOPMENT IS EXPECTED TO GENERALLY REMAIN WEAK.

MODELS SUGGEST SOUTHERLY LOW-LEVEL JET WILL STRENGTHEN ALONG THE
TEXAS GULF COAST LATE FRIDAY EVENING WITH APPROACH OF SHORT WAVE
TROUGH.  THIS WILL ENHANCE LOW-LEVEL MOISTURE RETURN/WARM
ADVECTION...AS WELL AS VERTICAL SHEAR PROFILES...NEAR COASTAL
AREAS...WHERE BOUNDARY LAYER DEW POINTS NEAR 70F WILL LIKELY SUPPORT
WEAK SURFACE-BASED INSTABILITY.  LOW-LEVEL HODOGRAPHS MAY BRIEFLY
BECOME SUFFICIENT FOR ISOLATED SUPERCELLS...BEFORE LOW-LEVEL JET
AXIS AND STRONGER LOW-LEVEL FORCING SHIFT INTO THE WESTERN GULF OF
MEXICO OVERNIGHT.

OTHERWISE...A GRADUAL STRENGTHENING OF MID-LEVEL FORCING FOR UPWARD
VERTICAL MOTION...IN EXIT REGION OF JET STREAK PROGRESSING THROUGH
BASE OF LARGER SCALE TROUGH...WILL SPREAD FROM THE LOWER RIO GRANDE
VALLEY TOWARD THE LOWER MISSISSIPPI VALLEY LATE FRIDAY EVENING INTO
EARLY SATURDAY.  THIS WILL SUPPORT HIGHEST PROBABILITIES OF
THUNDERSTORMS AND MOST VIGOROUS CONVECTIVE DEVELOPMENT FROM EAST
TEXAS INTO PARTS OF LOUISIANA AND ARKANSAS.  GIVEN PROGGED
MOIST/NEAR SATURATED SOUNDINGS WITH CAPE ONLY ON THE ORDER OF A FEW
HUNDRED J/KG...SEVERE THREAT SEEMS RATHER LOW.

..KERR.. 01/15/2004

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.

$$